Whey Protein Isolate

Bulk Nutrients Whey Protein Isolate (WPI) is ultra-high in protein and is certified as being sourced from grass fed, hormone free cows.

4.8 from 1405 reviews. Read all reviews or leave your own.
  • Lactose Free
  • Gluten Free Ingredients
  • Vegetarian
  • Vegan
  • Taste
  • Mixability
  • Effectiveness
  • Value for Money

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Buy in bulk and save

  • 1kg = AU$36
  • 2kg = AU$69 (AU$34.50 each)
  • 3kg = AU$97 (AU$32.33 each)
  • 4kg = AU$124 (AU$31.00 each)
  • 5kg = AU$149 (AU$29.80 each)
  • 10kg = AU$289 (AU$28.90 each)
  • 15kg = AU$425 (AU$28.33 each)
  • 20kg = AU$549 (AU$27.45 each)

Highest Protein

Taken post workout

Ultra low fats & carbs

Whey Protein Isolate (WPI) Protein Powder

Bulk Nutrients' Whey Protein Isolate (WPI) comes from grass-fed, hormone (rbST) free cows. It is a low-temperature cross and ultra-filtered whey protein which remains completely undenatured.

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We believe it is one of the purest Whey Protein Isolates on the market, with high levels of protein and lower levels of fats, carbohydrates and sodium.

Our Whey Protein Isolate is naturally rich in amino acids, particularly branched chain amino acids (BCAAs) and essential amino acids (EAAs) which support optimum muscle growth.

Why should you use Whey Protein Isolate (WPI)?

Bulk Nutrients' WPI is an exceptionally pure protein source, with much of the fat and lactose normally found in Whey Protein Concentrate filtered out.

  • WPI is fast absorbing and can help build lean muscle
  • Taken post workout, WPI assists in recovery
  • WPI can help to increase protein synthesis
  • Whey Protein Isolate can help to boost the immune system
  • Bulk Nutrients WPI is low in fats and carbs, and has a neglible lactose content

A great selection of WPI flavours on offer...

Bulk Nutrients uses only the strongest sweetener available in our flavoured Whey Protein Isolate, which ensures an exceptionally pure finished product.

With flavours on offer like Chocolate Whey Protein Isolate, Vanilla WPI, Banana Whey Protein Isolate, Peppermint Slice Whey Protein Isolate, Choc Honeycomb WPI and Salted Caramel Whey Protein Isolate to name a few.

And, because we use the strongest flavours available, we only need to include them as a fraction of the overall product which ensures an exceptionally pure WPI from Bulk Nutrients.

Watch Lindsay and Sam chat about Bulk Nutrients' WPI

WPI vs WPC, which is better?

WPI and WPC come from the same source, here are the benefits they both offer.

  • WPI and WPC are both rapidly absorbing proteins
  • Both WPI and WPC are great to consume after training
  • They both contain minimal fats and carbohydrates per serve
  • Both offer a great range of delicious flavours

The main difference... WPI is a more refined version of WPC and because of this offers significantly less lactose per serve.

So, if you are very sensitive to lactose and can’t live without whey, or after a higher protein hit then give WPI a go!

WPI stacks well with other supplements in shakes...

Bulk Nutrients’ WPI is great to have in a protein shake with other muscle building and performance-based supplements. We believe it is best used with...

So if you want the fastest absorbing and most bioavailable protein source, choose Bulk Nutrients WPI.

Fast shipping on Whey Protein Isolate

At Bulk Nutrients we offer $7 flat rate shipping and express postage for all orders 3.5kgs and under.

It's a very regular occurance for Bulk Nutrients customers in captial cities to order one afternoon and have their order on their doorstep the following morning!

Bulk Nutrients’ WPI is an all round protein

Whey Protein Isolate (WPI) is an all round protein source, so it caters for everyone from endurance athletes to strength athletes.

WPI is great to aid recovery, strength and muscle levels as well as boosting the immune system.

Directions & Ingredients


30 grams (approximately 1 level scoop) after training for maximum nutritional benefit, or anytime during the day for a low fat snack replacement or to boost your protein intake.

Directions for Whey Protein Isolate

Combine powder with 300-400ml of water or low fat milk and consume immediately.

We suggest you check out Protein Flavour & Sweetness Tweaking for information on how best to mix WPI.


Cross and Ultra Filtered Whey Protein Isolate (WPI), Flavour, Sweetener (Sucralose).

  • Chocolate based flavours (Chocolate, Choc Honeycomb, Peppermint Slice) contain cocoa.
  • Raw (Unflavoured) contains zero sweeteners or flavourings.


Contains Dairy, Soy Lecithin.

Soy Lecithin is added by the raw whey manufacturer to aid mixability. The inclusion rate is extremely low and will not affect those with allergies.


Keep well sealed, protect from moisture, light and heat.

Bulk Nutrients is proudly Australian owned and operated with all products developed, blended and packed locally in our facility in Grove, Tasmania. Find out more!

Frequently Asked Questions about WPI

How does Whey Protein Isolate taste?

WPI is flavoured and is generally considered to have a pleasant taste.

What is made from?

Whey Protein Isolate product is a protein derived from milk.

Are samples available of this product?

Yes, you can request a free sample of Whey Protein Isolate from our Free Sample page.
Iced Coffee Samples will be available in the coming weeks.

How is it packaged?

Bulk Nutrients' Whey Protein Isolate is packaged in resealable 1kg pouches.

Is the packaging for this product recyclable?

Yes! The bag can be recycled by placing it in the REDcycle drop off point bins. The included scoop can be recycled as a hard plastic in your local council pickup.

If you'd like more information, check this article which breaks down how Bulk's various products' packaging can be recycled.

Can I receive a discount buying more than one of this product at once?

Absolutely! Price breaks for Whey Protein Isolate begin when you purchase 2 units of any flavour. Just add more than that to your cart to see the savings.

Whey Protein Isolate Recipes

As it's so versatile, any recipe that uses a Bulk Nutrients protein can have it substituted for WPI.

That said, here are some of our favourite recipes using Bulk Nutrients WPI

Whey Protein Isolate Lab Testing Results

At Bulk Nutrients we take our products’ purity very seriously.

To maintain our Whey Protein Isolate’s consistent high quality, we send a cross section of our product range away to be tested for protein purity by the National Measurement Institute (NMI) each month.

The NMI is a laboratory run by the Australian Government, which is used for police forensic testing, ASADA drug screening and by multinational food manufacturers for quality and safety testing.

NMI has conducted many hundreds of tests on Bulk Nutrients products for more than 6 years.

Lab testing results for Whey Protein Isolate (WPI).


  • NEW

WPI Nutrition Panels

Chocolate Based Flavours Nutrition Information
Servings per 1kg package: 33 Servings size: 30g
Average Quantity Per Serving Average Quantity Per 100g
Energy (kj) 480 1598.4
Protein (g) 25.5 85.2
Fats (g) 0.5 1.7
  (saturated) (g) 0.4 1.2
Carbohydrates (g) 1.2 3.9
  (sugars) (g) 0.3 1.0
Sodium (mg) 55 182.8
Vanilla Nutrition Information
Servings per 1kg package: 33 Servings size: 30g
Average Quantity Per Serving Average Quantity Per 100g
Energy (kj) 481 1602
Protein (g) 26.6 88.5
Fats (g) 0.3 1.0
  (saturated) (g) 0.2 0.7
Carbohydrates (g) 0.9 2.9
  (sugars) (g) 0.2 0.8
Sodium (mg) 54 179
Banana Nutrition Information
Servings per 1kg package: 33 Servings size: 30g
Average Quantity Per Serving Average Quantity Per 100g
Energy (kj) 481 1604
Protein (g) 26.6 88.8
Fats (g) 0.3 1.0
  (saturated) (g) 0.2 0.8
Carbohydrates (g) 0.8 2.7
  (sugars) (g) 0.2 0.7
Sodium (mg) 54 179
Cookies & Cream Nutrition Information
Servings per 1kg package: 33 Servings size: 30g
Average Quantity Per Serving Average Quantity Per 100g
Energy (kj) 482 1607
Protein (g) 26.6 88.5
Fats (g) 0.3 1.0
  (saturated) (g) 0.2 0.7
Carbohydrates (g) 0.9 3.0
  (sugars) (g) 0.4 1.4
Sodium (mg) 54 179
Iced Coffee Nutrition Information
Servings per 1kg package: 33 Servings size: 30g
Average Quantity Per Serving Average Quantity Per 100g
Energy (kj) 473 1577
Protein (g) 26.0 86.8
Fats (g) 0.3 1.1
  (saturated) (g) 0.1 0.2
Carbohydrates (g) 1.0 3.3
  (sugars) (g) 0.2 0.6
Sodium (mg) 54 181
Raw (Unflavoured) Nutrition Information
Servings per 1kg package: 33 Servings size: 30g
Average Quantity Per Serving Average Quantity Per 100g
Energy (kj) 492 1640
Protein (g) 27.0 90.0
Fats (g) 0.4 1.2
  (saturated) (g) 0.3 1.0
Carbohydrates (g) 0.7 2.4
  (sugars) (g) 0.2 0.6
Sodium (mg) 47 156
Salted Caramel Nutrition Information
Servings per 1kg package: 33 Servings size: 30g
Average Quantity Per Serving Average Quantity Per 100g
Energy (kj) 479 1595
Protein (g) 26.3 87.8
Fats (g) 0.3 1.0
  (saturated) (g) 0.2 0.7
Carbohydrates (g) 1.0 3.2
  (sugars) (g) 0.3 0.9
Sodium (mg) 122 406
Strawberry Nutrition Information
Servings per 1kg package: 33 Servings size: 30g
Average Quantity Per Serving Average Quantity Per 100g
Energy (kj) 481 1603
Protein (g) 26.4 87.9
Fats (g) 0.3 1.0
  (saturated) (g) 0.2 0.7
Carbohydrates (g) 1.1 3.6
  (sugars) (g) 0.2 0.7
Sodium (mg) 53 177
Typical Whey Protein Isolate Amino Acid Profile
Typical Amino Acid Profile Avg Qty Per Serve Avg Qty Per 100g
Alanine (mg) 1379 4597
Arginine (mg) 726 2420
Aspartic Acid (mg) 3023 10077
Cysteine (mg) 967 3223
Glutamic Acid (mg) 4257 14190
Glycine (mg) 435 1450
Histidine (mg) 484 1613
Isoleucine (mg) 1524 5080
Leucine (mg) 3459 11530
Lysine (mg) 2709 9030
Methionine (mg) 580 1933
Phenylalanine (mg) 919 3063
Proline (mg) 1088 3627
Serine (mg) 1088 3627
Threonine (mg) 1282 4273
Tryptophan (mg) 580 1933
Tyrosine (mg) 1016 3387
Valine (mg) 1354 4513

Formulated Supplementary Sports Food. Not suitable for children under 15 years of age or pregnant women. Should only be used under medical or dietetic supervision. This product is not a sole source of nutrition and should be consumed in conjunction with a nutritious diet and appropriate physical training or exercise program.

About Whey Protein Isolate

Whey Protein Isolate (WPI) is considered the industry standard for dairy protein quality and is made during the cheese making process. As it’s the most highly refined version of whey protein, Whey Protein Isolate has the highest level of protein and the lowest level of fats and carbohydrates.

Containing only traces of lactose, it is easily digestible and can be enjoyed by those with sensitive stomachs. Whey Protein Isolate has high levels of branched chain amino acids and essential amino acids, with a thorough spread of conditional and non-conditional amino acids.

Whey Protein Isolate FAQs

Why is WPI the best choice?

Whey Protein has the highest biological value of any protein source and WPI is the most processed and purest form of Whey Protein.

WPI contains around 1% fats, 1% carbohydrates and around 90% of protein. As it is rapidly absorbed, it is ideal post workout, especially when training in a fasted state.

Is WPI lactose free?

WPI contains small amounts of lactose which usually means it is suitable for lactose sensitive individuals. People with complete lactose malabsorption may still have trouble tolerating the lactose in whey protein isolate.

Comparatively though WPI contains very little lactose, at approximately 0.3 grams per serve it has forty times less lactose than a glass of milk.

Does WPI contain gluten?

Gluten is not naturally occurring in any of the ingredients in our WPI, though we do process other gluten containing ingredients in our facility.

How many serves of WPI should I have each day?

The answer here will depend on your weight, energy levels and goals.

Most athletes and active people aim to consume 2 grams of protein per kilogram of bodyweight per day. For an 80kg person, this equals 160 grams of protein. Two WPI shakes a day would contribute 52g of protein to this total, leaving approximately 108 grams of protein to be consumed through general food sources.

Protein from protein shakes should be one of multiple protein sources you consume, not the only one.

What is the standard dose of WPI powder?

30 grams is the generally accepted standard dose of WPI protein powder, as this yields between 25 and 28 grams of pure protein.

How long after a workout should I have WPI?

For optimal recovery and muscle growth, it’s generally recommended to take Whey Protein Isolate within 20-60 minutes after exercise.

Why is WPI better than eating tuna, meat or drinking milk?

Like other powdered protein sources, WPI is great value for money and can be very convenient.

With a long shelf life (usually up two years), WPI is extremely stable and can be stored, carried and consumed easily unlike a tin of tuna or steak.

WPI contains only trace amounts of fats and carbohydrates, as opposed to most high protein foods which contain these in higher amounts.

How soon should I drink WPI after mixing it with water?

While WPI is very stable in powdered form this changes when mixed with water. Once mixed with water, WPI should be consumed within an hour. It can last more than 24 hours once blended with water if refrigerated.

Whey Protein Isolate Reviews

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